Databases Flashcards
Structured Data
data is often organized to support transactional and analytical applications. Structured data is most commonly stored in relational databases but can also be stored in non-relational databases.
Unstructured Data
data is not organized in any distinguishable or predefined manner. Common stores for unstructured data are non-relational key-value databases. Unstructured data is full of irrelevant information, which means data needs to first be processed to perform any kind of meaningful analysis
Semistructured
data can be just as predictable and organized as structured data. The difference is that semistructured data is flexible and can be updated without the requirement to change the schema for every single record in a table. non-relational stores
OLAP
Relational DB online Transactional Processing. Optimize for Read
OLTP
Relational DB Online Transaction Processing. Optimize for Write
Aurora
Aurora is MySQL and PostgreSQL compatible.
log structured distributed storage layer
auto 6 copies of data across AZs
backed up to S3 with snapshots
serverless
Redshift
Amazon Redshift delivers 10 times faster performance than other data warehouses by using machine learning, massively parallel query execution, and columnar storage on high-performance disk. You can set up and deploy a new data warehouse in minutes. Run queries across petabytes of data in your Amazon Redshift data warehouse and exabytes of data directly from your data lake built on Amazon Simple Storage Service (Amazon S3) with Amazon Redshift Spectrum.
Steps to create RDS
- VPC
- Subnets (requires 2 in 2 different AZs)
- EC2
- Security Group
Aurora
- DB Instance Class (mem optimized or burstable)
2
Foreign Key
Used to create relationships between tables in a relational database
updating the schema
Adding a column in a nonelational db is not required to update. Relational update is required.
T/F Nonrelational databases are optimized for storage?
False: they are optimized for compute.
Which DB type scales vertically
Relational
T/F both types of DB use OLTP and OLAP?
Flase. Only relations uses OLAP
Key Value
Uses in Non-relational
Typicall stored in one table.
Can handle varied data
flexible